This invention relates generally to tote containers and cartons folded from a generally planar blank of sheet material and having a retaining rim, and particularly to an tote container design which permits an open-top tote container to be integrally locked and cross stacked on a like open-top tote container in a non-aligned vertical column.
A multiplicity of various tote containers, cartons, and boxes are known to the art, each having features making that container, box, or carton more suitable for particular applications.
In particular, a representative example of an open-top tote container folded from a blank of three-ply corrugated plastic sheet material and having a metal retaining rim is disclosed in U.S. Pat. No. 4,682,727.
In general, such tote containers are designed to be nested within one another, and therefore have angled or tapered side walls, and may include a stacking shoulders which prevent a container nested within a like container from becoming permanently wedged therein.
Another example of such an open-top tote container which may be selectively collapsed and which has a portion of the rim elevated to form handle grips is disclosed in the pending U.S. patent application Ser. No. 07/041,927.
In order to accommodate stacking such tote containers or cartons, various modifications have been incorporated to support and align a plurality of like tote containers in a vertical column, such as lid flaps, stacking tabs, or hand grips having corner supports and raised rims. Representative examples of these features may be seen in U.S. Pat. Nos. 4,709,852 and 4,119,265, and the pending U.S. patent application Ser. No. 6/911,993.
Such arrangements generally require the alignment of the tote containers when stacked in a vertical column, and thereby block or prevent items from being added to or removed from the receptacle regions of the lower tote containers. Further, stacking such tote containers require that some support apparatus be positioned or engaged to hold the top container, such as folding down the lid flaps or adding a rack or tray support.